2011 National Question 4 Single-choice Differentiating 2011_退役省自主命题 (2011·文) 3.圆 $x^{2}+y^{2}-4 x+6 y=0$ 的圆心坐标是 A. $(2,3)$B. $(-2,-3)$C. $(-2,-3)$D. $(2,-3)$ Answer keyD ☆ SaveCan't do it, show the explanation查看原卷 →